python - 函数购物车(含文件读取)

作业需求:

1，启动程序，用户可选择四个选项：登录，注册，购物，退出。
2，用户注册，用户名不能重复，注册成功之后，用户名密码记录到文件中。
3，用户登录，用户名密码从文件中读取，进行三次验证，验证不成功则退出整个程序。
4，用户登录成功之后才能选择购物功能进行购物，购物功能（就是将购物车封装到购物的函数中）。
5，退出则是退出整个程序。

#auth_Mouni
#date 2019-01-18
def man():
while 1:
choise = input("[1]登录 [2]注册 [3]购物 [4]退出 请选择:>>")
if choise == "1":
login()
elif choise == "2":
register()
elif choise == "3":
print("请先登录,再进行购物".center(15,"*"))
login()
elif choise == "4":
print("已退出系统".center(15,"*"))
break
else:
print("输入有误重新输入")

def register():
freg = open('pd_file', 'a+', encoding='utf-8')
freg.seek(0)
users_info = {}  # 定义存放用户名，密码的 字典
for line in freg.readlines():        # 逐行读取用户名，密码，并存储到字典中
users = line.strip().split(',')
users_info[users[0]] = users[1]

while True:
username = input('请注册用户名：>>').strip()
if username in users_info.keys():
print('用户名已存在，请重新注册')
man()
else:
password = input('请输入密码：').strip()  # 确认两次密码输入
cpasswd = input('请确认密码：').strip()
if username and password and cpasswd:
if password != cpasswd:
print('两次输入密码不一致，请重新注册！')
register()
else:
freg.write(username + ',' + password + '\n') # 写入密码文件
print('注册成功')
break
freg.close()

# def login():
#     with open('pd_file_1', 'r', encoding='utf-8') as f:
#         users_info = {}
#         username = input('请输入用户名：>>')
#         for line in f.readlines():
#             users = line.strip().split(',')
#             users_info = {"name": users[0], "pws": users[1]}  # 循环获取 帐号和密码
#             # print("用户名:%s  密码%s" % (users_info['name'], users_info['pws']))  # 用户名 密码
#             # print(users_info["pws"])   # 密码
#             if username == users_info["name"]:  # 判断用户是否存在
#                 while 1:
#                     password = input('请输入密码：')
#                     if password == users_info["pws"]:  # 判断用户密码是否正确
#                         print("登录系统成功".center(15,"*"))
#                         shoping()
#                     else:
#                         n = 3
#                         while n > 0:  # 三次错误密码循环
#                             n -= 1
#                             password = input('用户或密码错误,请重新输入,还有%s机会:>>' % n)
#                             if n == 1:
#                                 print("用户或密码错误,注册或重新登录")
#                                 man()
#                     break
#         else:
#             flog = "不存在" # 标记用
#         if flog == "不存在":
#             print("用户不存在,请注册")
#             man()
def login():
with open('pd_file', 'r', encoding='utf-8') as f:
users_info = {}
username = input('请输入用户名：>>')
for line in f.readlines():
users = line.strip().split(',')
users_info = {"name": users[0], "pws": users[1]}  # 循环获取 帐号和密码
# print("用户名:%s  密码%s" % (users_info['name'], users_info['pws']))  # 用户名 密码
# print(users_info["pws"])   # 密码
if username == users_info["name"]:  # 判断用户是否存在
while 1:
password = input('请输入密码：>>')
if password == users_info["pws"]:  # 判断用户密码是否正确
print("登录系统成功".center(15,"*"))
shoping()
else:
n = 3
while n > 0:  # 三次错误密码循环
n -= 1
print('用户或密码错误,请重新输入,还有%s机会' % n)
password = input('请输入密码:>>')
if password == users_info["pws"]:  # 判断用户密码是否正确
print("登录系统成功".center(15, "*"))
shoping()
if n == 1:
print("用户或密码错误,注册或重新登录")
man()
break
else:
flog = "不存在" # 标记用
if flog == "不存在":
print("用户不存在,请注册")
man()

def shoping():
product_lst = [
{"name": " 电脑 ", "price": 1999,"ID":0},
{"name": " 鼠标 ", "price": 10,"ID":1},
{"name": " 游艇 ", "price": 20,"ID":2},
{"name": " 美女 ", "price": 998,"ID":3}]
shop_car = []
cost_money = 0
ID_lst = []
print("欢迎光临幸福超市".center(15,"*"))
while 1:
salary = input("输入金额进行购物:>>")
if salary.isdigit():
salary = int(salary)
break
else:
print("输入金额有误,请重新输入")

chajia = 0
while 1:
print("买商品信息如下".center(20, "*"), "\nID", "商品名称".center(9, " "), "价格")
for i in range(len(product_lst)):
print(i, product_lst[i]["name"].center(11, " "), product_lst[i]["price"])  # 输出商品列表信息
# print(i + 1, product_lst[i]["name"].center(11, " "), product_lst[i]["price"])  # 输出商品列表信息

choise = input("输入ID将商品加入购物车,
结算 [Q]退出:>>")
if choise.isdigit():  # 开始购物
index = int(choise)  # 购物车的 ID 下标
if int(index) < 0 or int(index) >= len(product_lst):
print("选择有误,重新选择:>>")
continue
else:
for item in shop_car:
if item["ID"] == index:
item["totle"] += 1
ID_lst.append(product_lst[index]["ID"])
break
else:  # 第一次商品加入购物车 增加ID项  和 数量项
shop_car.append({"ID": index, 'name': product_lst[index]['name'], "price": product_lst[index]['price'],"totle": 1})
ID_lst.append(product_lst[index]["ID"])
elif choise.upper() == "Q":  # 退出时 不计算商品
print("退出购物商城,无购物".center(15, "*"))
man()
elif choise == "n":  # 结算 商品
while 1:
for i in range(len(shop_car)):  # 打印购物车内商品信息
cost_money += shop_car[i]["price"] * shop_car[i]["totle"]
while 1:  # 进入移除商品循环
if len(shop_car) == 0:
print("购物车内无商品")
print("购物车已清空","\n无消费,余%s元" % (int(salary) - int(cost_money)))
man()
if int(salary) > int(cost_money):  # 购物金额充足时
print("您购买商品信息如下".center(20, "*"), "\n商品名称", "数量".center(10, " "), "价格")
for i in range(len(shop_car)):
print(shop_car[i]["name"], str(shop_car[i]["totle"]).center(12, " "), shop_car[i]["price"])
print("共消费%s元,余%
20000
s元" % (int(cost_money), int(salary) - int(cost_money)))
exit()
else:  # 购物金额不足时
chajia = int(salary) - int(cost_money)  # 差的钱数

print("购物金额不足,请移除部分商品,还差%s元" % (chajia))
print("ID", "商品名称".center(5, " "), "数量".center(7, " "), "价格")
for i in range(len(shop_car)):  # 打印购物车内要移除的商品列表
print(shop_car[i]["ID"], shop_car[i]["name"].center(7, " "),
str(shop_car[i]["totle"]).center(9, " "), shop_car[i]["price"])  # 输出商品列表信息
while 1:
choise = input("输入移除商品ID,退出商城请按[Q]:>>")  # 选择移除商品 ID
if choise.isdigit():
choise = int(choise)
if choise >= 0 and choise in ID_lst:  # 存在一个小BUG
break
else:
print("输入ID有误,请重新输入")
continue
elif choise.upper() == "Q":
man()
else:
print("输入ID有误,请重新输入")
for item in shop_car:
if item["ID"] == choise and item["totle"] == 1:
cost_money -= item["price"]  # 商品为1件时移除 花费钱还回来
shop_car.remove(item)
ID_lst.remove(int(item["ID"]))

elif item["ID"] == choise:  # 商品数量 减少
cost_money -= item["price"]
item["totle"] -= 1
ID_lst.remove(int(item["ID"]))

exit()
else:
print("输入有误,请重新输入:>>")

def quit():
print("已退出系统".center(15, "*"))
exit()

man()```